Winegrowers Supplies   - Notes on using Willmes WP Pneumatic grape presses:

Compressor: The oil needs to be changed every 10 years; use a gear oil.

Once a year - unscrew the water release valve (under the outlet tube).

Press grease: the hand turned pieces could be replaced with grease nipples.

Press filling/emptying doors: these must always be fitted in the same positions that they are initially; there are pressure vents at the ends.

With a 1000 litre Press a complete filling should give 900 to 1000 litres of juice, including free run juice.

Normally 5 to 6 pressings are made, initially at bar then at 1 bar etc, progressively increasing it to 2 (or 3 bar). 'Crumbling' is carried out between each pressing, the pressure must be reduced to bar (or less) before crumbling.

To obtain the best quality juice it may be preferable not to use the full pressure available. Experiment with repeated pressings at 2 bar to see whether sufficient juice can be extracted at this pressure.

When 'crumbling' - up to a minutes rotation is sufficient to redistribute the grapes.
Rotation is in a clockwise direction (when standing at the control end).